1. Field of the Invention
The present invention generally relates to the field of telecommunications and to an apparatus and method for managing telephony-based services, such as routing and translations services. More particularly, the present invention relates to an intelligent or advanced application, such as an Advanced Intelligent Network (AIN) application, for routing a special or dedicated telephone number through multiple paths out of an AIN end office to a dedicated or special purpose telecommunications system, such as the Government Emergency Telecommunications Service (GETS).
2. Acronyms
The written description provided herein contains acronyms which refer to various communication services and system components. Although known, use of several of these acronyms is not strictly standardized in the art. For purposes of the written description herein, acronyms will be defined as follows:
10D--10 Digit Trigger PA0 AIN--Advanced Intelligent Network PA0 ACR--Alternate Carrier Routing PA0 CCIS--Common Channel Interoffice Signaling PA0 CCS--Common Channel Signaling PA0 CO--Central Office PA0 CIC--Carrier Identification Code PA0 CPR--Call Processing Record PA0 CPN--Calling Party Number PA0 DID--Direct Inward Dialing PA0 DLN--Dialed Line Number PA0 DRS--Data and Reports System PA0 EO--End Office PA0 FIM--Feature Interaction Manager PA0 ISCP--Integrated Service Control Point PA0 ISUP--ISDN User Part PA0 IXC--Interexchange Carrier PA0 LATA--Local Access and Transport Area PA0 MF--Multi-Frequency PA0 NANP--North American Numbering Plan PA0 NPA--Numbering Plan Area PA0 NXX--Central Office Code PA0 PIC--Primary Interexchange Carrier PA0 PRI--Primary Rate Interface PA0 PSTN--Public Switched Telephone Network PA0 SCE--Service Creation Environment PA0 SCP--Service Control Point PA0 SMS--Service Management System PA0 SRAS--Special Routing Access Service PA0 SS7--Signaling System 7 PA0 SSP--Service Switching Point PA0 STP--Signaling Transfer Point PA0 TAT--Termination Attempt Trigger PA0 TCAP--Transaction Capabilities Applications Part PA0 TG--Trunk Group PA0 TN--Telephone Number
3. Background Information
(a) Government Telecommunications Service (GETS)
GETS is a telecommunications system maintained by GTE and the federal government for use during emergencies. Specifically, the Numbering Plan Area (NPA) code of 710 was established for the special federal government telephone number 710-NCS-GETS (i.e., 710-627-4387). In the prior art, this telephone number was routed to GETS either through the Primary Interexchange Carrier (PIC) of the calling location for offices with a GETS service, or through AT&T for a calling location that has contracted with AT&T for Special Routing Access Service (SRAS).
A drawback of the above arrangement is that only a single telephone carrier is available for connecting any one node/office to GETS. However, during an emergency, the particular carrier may not be available and/or accessible. For example, a flood of calls to a disaster area, downed communication lines, or damage to the carrier itself may cause service outage or overload.
(b) Advanced Intelligent Networks
In recent years, Advanced Intelligent Networks (AIN) have provided a number of new telephone service features. The AIN evolved out of a need to increase the capabilities of the telephone network architecture to meet the growing needs of telephone customers or users. The AIN architecture generally comprises two networks, a data messaging network and a trunked communications network. The trunked communications network handles voice and data communications between dispersed network locations, whereas the data messaging network is provided for controlling operations of the trunked communications network.
An illustration of the basic components of AIN architecture is shown in FIG. 1. As shown in FIG. 1, Service Switching Points (SSP's) 64-70 are provided for sending and receiving data messages from a Service Control Point (SCP) 56 via Signaling Transfer Points (STP's) 58-62. The data messages are communicated to and from the SSP's 64-70 and the SCP 56 along a Common Channel Signaling (CCS) network 88. Each SSP 64-70 routes telephone calls between a plurality of dispersed network stations 172-186. For example, SSP's 64-70 may route a telephone call between a calling station (e.g., station 172) and a called station (e.g., station 184) through trunks 90 and customer lines 92 (e.g., telephone lines). Stations 172-186 may comprise various customer or terminal equipment, such as a telephone unit (wired, cellular or mobile), a facsimile machine, and/or a modem attached to a personal computer.
More information regarding AIN may be found in various publications. See, for example, Berman, Roger K., and Brewster, John H., "Perspectives on the AIN Architecture," IEEE Communications Magazine, February 1992, pp. 27-32, the disclosure of which is expressly incorporated herein by reference in its entirety.
A number of services or features provided by prior AIN or AIN-type intelligent networks relate to specialized call processing or recording of incoming calls and call traffic. For example, U.S. Pat. No. 5,583,926 discloses routing of calls to dedicated numbers. The subscriber can select an overflow routing option to provide a list of overflow routes or trunks to provide alternate routes within a single network to connect a call. The alternate routes may be available to the Primary Interexchange Carrier if the most direct route is overloaded.
A drawback of the above-noted patent is that while it establishes several routes to place calls to a carrier, it cannot route the call to an alternate carrier if the carrier is disabled or otherwise inaccessible. Further, prior systems do not permit a user or party to dial a dedicated number to optionally select a specific carrier and/or backup carriers to ensure completion of the call.